What is click fraud?

If you use AdWords or AdSense, you've probably heard of "click fraud", a new trend in the computer underworld.

But what is click fraud and how is it carried out?

AdSense provides a payment mechanism that pays a publisher (someone who has an AdSense banner on their site) a certain amount of money each time someone clicks on the advert. Consequently, click fraud is the practice of getting people to click on adverts in order to increase their revenue. There are people who create websites for the sole purpose of making money from Google's AdSense programme. These users achieve an astonishing number of clicks by using a variety of techniques, some of which are complicated and sophisticated and others that are simple and straightforward.

The use of so-called "hitbots" is one of the most complicated. These are computer programs that pretend to click on the links in AdSense adverts (there are also some that actually click on the banners). Google's AdSense protection method is far from ideal, and almost anyone can figure out how to get around it - ironically, by simply doing a Google search.

Another, more primitive method is to hire a large number of people in a poor country to click on the links on your website. This means that these people will sit and click on links all day to make you money. They come from impoverished countries like India and are willing to work for as little as $0.50 an hour. Of course, there is a catch to this method. If Google receives a large number of clicks from a single address, this address and the website on which the AdSense banner was displayed will be blocked and the fraudster can be sued.

To prevent this, many users use a large number of proxy servers that they click on. These are essentially Trojans that can be found on computers all over the world (although mainly in the USA). Even scarier, these clicks look like they're coming from a legitimate computer, making such scams extremely difficult to detect. And don't assume that this only happens once in a while. There is a lot of criminal activity in this area. In fact, there's so much that illegal activity can cause even more damage if search engine providers don't improve their security with programmes like AdSense.

Google has a strict policy against click fraud and has already sued those who have used such tactics. Whilst the search engine giant is doing everything it can to reduce the risk of click fraud, there is still plenty of room for improvement. It is thought that more than 20% of clicks following an AdSense link are made solely to obtain money from the person who paid for the advert. Some experts believe that the proportion of false clicks is much higher.

There are many other tactics of click fraud, such as groups of AdSense publishers clicking on each other's links (known as "click rings") or spamming individuals to get them to click on such links. Despite Google's efforts to keep click fraud under control, the situation is causing concern among AdWords customers.

Nevertheless, advertising via Google's AdSense is still more profitable for marketers than traditional, non-targeted advertising strategies. There are ways to protect yourself from such methods and all advertisers should be aware of them. For fear of click fraud, many marketers choose to stay away from the content network altogether.